The complaint was filed Thursday against the United Food and Commercial Workers International Union, The Wall Street Journal reported.

Walmart alleges the union is behind the protest plans. Workers have held rallies and picketed at Walmart stores and warehouses across the country for at least the last six months.

The protesters -- who complain of low wages, short hours and poor working conditions -- are members of OUR Walmart, or Organization United for Respect at Walmart, which was started in 2010 with financial support and advice from the UFCW.

OUR Walmart is "its own non-profit organized by Walmart workers and funded through dues that are voluntarily contributed," said UFCW spokeswoman Jill Cashen.

OUR Walmart has called for protests at 1,000 Walmart stores on Black Friday, which is one of Walmart's busiest shopping days.

"We cannot allow the UFCW to continue to intentionally seek to create an environment that could directly and adversely impact our customers and associates," Walmart spokesman David Tovar said.

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